Wireless cockpit routing has become one of the most requested features on road bikes, and Shimano delivers it at the 105 level with the ST-R7170 Di2 Dual Control Lever. The shift signals travel wirelessly from the levers to the rear derailleur, eliminating the need to run Di2 wires through handlebars, stems, and headsets. Two CR1632 coin cell batteries power each lever for 3.5 to 4 years of shifting before replacement, so there's no charging routine to remember. The ergonomic shape borrows directly from Dura-Ace development, with a raised hood peak and extended body that provides support whether you're on the hoods or in the drops.

Each lever ships with the matched BR-R7170 flat mount hydraulic caliper and pre-bled hose kit. The caliper design delivers 10% wider pad clearance than the previous generation, which reduces the likelihood of rotor rub and keeps things quiet during cornering or out-of-the-saddle efforts. Shimano's one-way bleeding process simplifies maintenance when the time comes. The included resin pads with cooling fins use ICE Technologies to manage heat on long descents, maintaining consistent lever feel even when the brakes are working hard.

Reach adjustment lets you position the lever blade closer or farther from the bar to fit your hand size. The E-TUBE app opens up button customization and Synchro-Shift configuration, allowing you to set up semi-automatic or fully automatic front shifting based on your rear cassette position. This is the same shifting logic that Dura-Ace and Ultegra Di2 systems use, just at a more accessible price point. The Servowave lever design provides quick initial pad contact followed by a wider modulation zone for precise braking control.... Read More